Gasoline compositions



3,468,640 GASOLINE COMPOSITIONS Maurice R. Barusch, Richmond, and George J. Kautsky,

El Cerrito, Calif, assignors to Chevron Research Company, a corporation of Delaware No Drawing. Filed Sept. 22, 1964, Ser. No. 398,440 Int. Cl. C10] 1/22 US. CI. 44-75 Claims ABSTRACT OF THE DISCLOSURE Gasoline for automotive use is improved by adding to it from about 30 to about 500 parts per one million parts of the gasoline of a particular oil-soluble quaternary ammonium hydroxide to reduce significantly the deposits due to blowby and puffback in the induction system, and particularly in the carburetor of spark-ignition engines.

The present invention relates to improved gasoline compositions for use in spark-ignition engines. In particular, it relates to gasoline compositions containing a detergent-action additive, which effectively reduces deposits forming in the operation of such engines in their induction systems, specifically in their carburetors.

Formation of deposits in the induction system of a spark-ignition engine and particularly in the throttle section of its carburetor tends to cause erratic idling and stalling of the engine, particularly when the engine has to run at idle for any significant length of time, as it occurs in automobiles and trucks in the midst of heavy city trafiic when they are subject to recurrent stop-and-go signals and also in services, such as taxicabs and door-to door deliveries.

Obviously, finding new, better and often more economical additives which would contribute to minimization and reduction of the aforementioned deposits is of a great interest to the automotive industry. The actual sources of such deposits interfering with the smoothness of engine operation are many and well-known; these are engines own blowby and puffback, exhaust from other automobiles, and other intake air contaminants. All of these sources have ben extensively referred to and discussed in the technical literature and patents.

Addition to gasoline of materials which would be likely to reduce or to eliminate completely the engine intake system and carburetor deposits is clearly preferable to periodic mechanical adjustment effected to compensate for the presence of these deposits in the induction system and to manual work of dismantling and reconditioning of the engine to remove the deposits.

We have discovered that by adding to gasolines, whether leaded or otherwise, a minor amount of from about 30 to about 500 ppm. (that is, parts per one million parts of the gasoline) of quaternary ammonium base soluble in oil and gasoline from a particular group of such bases as defined hereinafter by the general formula therefor, it becomes possible either to eliminate completely or at least to reduce significantly the aforementioned objectionable engine deposits and thus to improve the operation of the engine on the gasoline treated with such a base.

The group of quaternary ammonium bases effective according to the present invention includes all materials which correspond to the general formula:

in which R is a hydrocarbon radical of from to 24 carbon atoms, R and R represent a hydrocarbon radical 3,468,640 Patented Sept. 23, 1969 of from 1 to 24 carbon atoms, or yet maybe a hydroxyalkyl radical of two to three carbon atoms, or yet a hydroxy-terminated polyalkylene oxide radical containing from 2 to 4 alkylene oxide units with 2 to 3 carbon atoms in each unit (i.e. ethylene oxide, propylene oxide or trimethylene oxide).

The hydrocarbon radicals in the aforegiven formula, that is, R R and R may be acyclic, straight-chain or branched-chain alkyl, alkenyl, alkadienyl, alkapolyenyl and ar alkyl radicals, as well as alicyclic or aromatic hydrocarbon radicals. These radicals may be of the same kind, e.g., all myristyl, or they may be mixed radicals, such as are derived from different vegetable and/or animal source materials, for insance, hydrocarbon radicals derived from coconut oil, soya oil, cottonseed oil, olive oil, tallow and hydrogenated tallow. The presence of one long C -C and preferably C C hydrocarbon chain at least in the R radical of the formula is necessary in order to impart solubility in gasoline to the ammonium base. The other two radicals, R and R need not be the same as R although they may be the same, and, furthermore, they may be of a lower molecular weight. As a matter of fact, as mentioned already hereinabove, these radicals, R and R may be also derived from ethylene oxide, propylene oxide or trimethylene oxide; for instance, R and R may be hydroxyethyl, Z-hydroxypropyl, 3-hydropropyl, hydroxythoxyethyl and other like etherlinked radicals, provided the total number of carbons in such radicals does not exceed 12, and provided the number of alklene oxide units is less than 5.

While, as mentioned before, reduction of deposits may be obtained by adding from about 30 to about 500 ppm. (that is, from about 0.003% by weight to about 0.05% by weight), for all practical purposes and for the best performance, addition of from about 50 to about 300 p.p.m. (that is, from about 0.005 to about 0.03% by weight) of a quaternary ammonium hydroxide base corresponding to the foregiven general formula is preferred.

Many of the quanternary ammonium bases described hereinabove are commercially available materials, sold in the trade usually as solutions of 50% of such bases in mixed solvents consisting of hydrocarbons, alcohols and water.

They can be produced by various methods known in the art, for instance, by liberating the free base upon treating a quanternary ammonium salt, such as a halide or the like, with caustic. Particularly desirable ones from practicalpoint of view are those containing a long hydrocarbon radical of 12 to 18 carbon atoms.

In order to facilitate handling and to introduce these ammonium bases into the fuel, it is preferred to do so by using a concentrate of the ammonium base, for instance, by dissolving such a base in an appropriate organic solvent compatible with and boiling in the gasoline range, preferably in a hydrocarbon solvent, and desirably in an aromatic one, such as benzene, toluene, xylene or the various aromatic petroleum-base thinners. The concentrate of the quaternary ammonium base may also be formed by dissolving it in an alcohol, preferably in a C -C aliphatic alcohol, such as ethanol, isoprop'anol, methylisobutylcarbinol, and the like. Suitable mixtures of hydrocarbon solvents and alcohols may also be used to prepare the concentrates. In all events, the quantity of the solvent in such concentrates may range from as low as 10% up to about 70% by weight.

In addition to the quaternary ammonium bases, used as detergent-action additives in accordance with the present invention, other conventional additives may be present in small amounts in the gasoline, provided these additives have no adverse effect in the improvement attainable through the use of these ammonium bases. Thus, the gasolines may, and usually do, contain tetraalkyl lead antiknock additives, such as tetraethyl lead, tetramethyl lead, or the like, in small amounts from about 0.5 to 4.0 ml. per gallon. Furthermore, there may be present lead scavengers, dyes, inhibitOrs of sparkplug fouling, oxida tion inhibitors, surface-ignition suppressants, etc. To aid further the reduction of objectionable deposits by the action of ammonium bases, a non-volatile oil, such as a mineral lubricating oil or a petroleum spray oil or the like, may be added, and this non-volatile oil then acts as a carrier for the deposits loosened up and displaced by the quaternary ammonium bases. Fro-m 0.005 to 0.5% by volume of such an oil is found to aid effectively in the deposit removal achieved by the additive.

A specially developed Carburetor Cleanup Test was employed to determine the deposit-removing or detergent-action quality of gasolines improved by the addition of quaternary ammonium bases in accordance with the invention. This test represents a modification of the Glass Throttle Body Test, described in the technical literature, fro instance, in U.S. Patent 2,839,272, issued to Lindstrom et al. on June 18, 1958. In this modified test, a six-cylinder engine of a Plymouth automobile is set up in the laboratory, its carburetor being provided with a removable glass throttle body section between the float section and the cast iron throttle body. This glass section represents a tube A1" thick, of approximately 1%" inside diameter and about 1%"2" long. A timer formed by a constant-speed electric motor and a magnetic clutch is provided to operate the engine in cycles with idle periods of 7.5 minutes each, followed by five accelerations to 2000 r.p.m. The engine is started on leaded base gasoline fuel (1.5 ml. of tetraethyl lead per gallon), which contains no surface-active (detergent) additives; and the engine is run for four hours, the blowby fumes being vented from the crankcase to the carburetor air inlet. Thereafter, the engine is stopped, the glass body is removed, and both sides of it are photographed. The dirty glass throttle body is reinstalled, and the engine run for one hour on the same leaded base gasoline, but this time it is compounded with the quaternary ammonium base additive of the invention. During this phase of the test the blowby fuels are vented to the carburetor. After one hour, the engine is stopped, the glass body is again removed and photographed. The effectiveness fo the fuel containing the added quaternary ammonium base in cleaning up the deposit is estimated visually.

In the following series of tests illustrative of the invention, three representative quaternary ammonium bases were added to the base gasoline. These were commercially available materials: soya trimethyl hydroxide, dioleyldimethyl ammonium hydroxide, and oleyldiethoxymethyl ammonium hydroxide, sold under the registered trademarks Arquad S-OH, Arquad 2OOH and Ethoquad O/12-OH.

The table below lists the concentration of each of these materials in p.p.m., as used in the test, and the corresponding rate of carburetor cleanup in percent.

PERFORMANCE OF QUATERNARY BASES IN CARBURE. TOR CLEANUP TEST Concen- Carburetor tration, cleanup, Compounds p.p.n1. percent Soya trimethyl ammonium hydroxide... 30 30 60 55 Dioleyldimethyl ammonium hydroxide.-. 13% 5% o 9 Oleyldiethoxymethyl ammonium hydroxide 50 60 Do 100 85 accordance with the invention, but, as a matter of fact, remove deposits existing in the carburetor before the beginning of the test, and thus enable a satisfactory engine operation for much longer periods of time between carburetor overhauls than otherwise would be expected.

In conclusion, it would be apparent to those skilled in the art that many modifications of the invention may be made without departing from the spirit and scope thereof, the materials in the examples of the specifications being offered solely by way of illustration, so that, accordingly, other equivalent quaternary nitrogen bases may be employed in practicing the invention within the purview of the following claims:

What is claimed is:

1. An improved gasoline composition comprising a major proportion of a hydrocarbon base fuel boiling in the boiling range of gasoline and from about 0.003 to about 0.05% by weight of an oil-soluble quaternary ammonium hydroxide base of the formula wherein R is a hydrocarbon radical of from 10 to 24 carbon atoms, R and R are selected from the group consisting of hydrocarbon radicals of from 1 to 24 carbon atoms, hydroxyalkyl radicals of from 2 to 3 carbon atoms, and hydroxy-terminated polyalkylene radicals formed by C -C alkylene oxide untis.

2. A composition as defined in claim 1, wherein R is a hydrocarbon radical of from 12 to 22 carbon atoms.

3. The composition as defined in claim 1, wherein the quaternary ammonium base is present in an amount from about 0.005 to about 0.03 by weight.

4. A detergent additive concentrate capable of being incorporated into gasoline, which comprises an organic solvent boiling in the boiling range of gasoline and selected from the group of hydrocarbon solvents and C -C aliphatic alcohols, and, dissolved therein, from about to about 30% by weight of an oil-soluble quaternary ammonium hydroxide base of the formula:

wherein R is a hydrocarbon radical of from 10 to 24 carbon atoms, and R and R are selected from the group consisting of hydrocarbon radicals of from 1 to 24 carbon atoms, hydroxyalkyl radicals of 2 to 3 carbon atoms and hydroxy-terminated polyalkylene radicals formed by C -C alkylene oxide units, the number of these units not exceeding four.

5. An additive concentrate as defined in claim 4, wherein the radical R, in the formula of the quaternary ammonium hydroxide base is a hydrocarbon radical of 12 to 22 carbon atoms.

References Cited UNITED STATES PATENTS 2,599,127 6/1952 Resuggan 252-l06 3,008,813 12/1961 Siegel 44---72 3,033,665 5/1962 Gaston et al.

3,317,291 5/ 1967 Marsh et al. 4472 OTHER REFERENCES Surface Active Agents and Detergents, by Schwartz et al., vol. II, copyright 1958, p. 197.

PATRICK P. GARVIN, Primary Examiner Y. H. SMITH, Assistant Examiner U.S. Cl. X.R. 

